The vanes of compressor rotors are sometimes damaged, in particular when solid bodies enter the gas flow passage and strike these vanes. They must then be replaced. In ordinary engines, the vanes are mounted in the grooves of the rotor, from which they can be separately removed by eliminating the joints and plates which stop them from sliding in the grooves, and after having opened the housing of the stator of the compressor or after having separated it from an adjacent housing which extends it and after having brought the rotor out of the housing by a sufficient length so as to reveal the damaged vane.
Today, it is essential that the rotor is produced in the form of monobloc vaned disks (MVD) assembled together, or by incorporating these disks with ordinary rotors whose vanes are movable. In both these cases, there are certain advantages, as these disks, whose vanes thus form a single piece with the cylindrical or conical casing to which they are adjusted, have better resistance to both stresses and vibrations. They thus make it possible to lighten the rotor. But they need to be fully replaced if one of their vanes becomes damaged, this being acceptable when the production cost of a replacement disk is taken into consideration, but requires freeing the disk, not only from the housing of the stator, but also from the shaft lines it surrounds.